LXR linux/mm/failslab.c

   1// SPDX-License-Identifier: GPL-2.0
   2#include <linux/fault-inject.h>
   3#include <linux/slab.h>
   4#include <linux/mm.h>
   5#include "slab.h"
   6
   7static struct {
   8        struct fault_attr attr;
   9        bool ignore_gfp_reclaim;
  10        bool cache_filter;
  11} failslab = {
  12        .attr = FAULT_ATTR_INITIALIZER,
  13        .ignore_gfp_reclaim = true,
  14        .cache_filter = false,
  15};
  16
  17bool __should_failslab(struct kmem_cache *s, gfp_t gfpflags)
  18{
  19        /* No fault-injection for bootstrap cache */
  20        if (unlikely(s == kmem_cache))
  21                return false;
  22
  23        if (gfpflags & __GFP_NOFAIL)
  24                return false;
  25
  26        if (failslab.ignore_gfp_reclaim &&
  27                        (gfpflags & __GFP_DIRECT_RECLAIM))
  28                return false;
  29
  30        if (failslab.cache_filter && !(s->flags & SLAB_FAILSLAB))
  31                return false;
  32
  33        return should_fail(&failslab.attr, s->object_size);
  34}
  35
  36static int __init setup_failslab(char *str)
  37{
  38        return setup_fault_attr(&failslab.attr, str);
  39}
  40__setup("failslab=", setup_failslab);
  41
  42#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
  43static int __init failslab_debugfs_init(void)
  44{
  45        struct dentry *dir;
  46        umode_t mode = S_IFREG | 0600;
  47
  48        dir = fault_create_debugfs_attr("failslab", NULL, &failslab.attr);
  49        if (IS_ERR(dir))
  50                return PTR_ERR(dir);
  51
  52        debugfs_create_bool("ignore-gfp-wait", mode, dir,
  53                            &failslab.ignore_gfp_reclaim);
  54        debugfs_create_bool("cache-filter", mode, dir,
  55                            &failslab.cache_filter);
  56
  57        return 0;
  58}
  59
  60late_initcall(failslab_debugfs_init);
  61
  62#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
  63